I don’t know if you came up with a solution for this, but I have a similar question about how to have the vendor except and process the payments.
I suspect It doesn’t work in person because the plugin is designed for the website owner to process all vendor store product sales, and thus pay the vendor a “commission” from their sales.
If the store vendor processed their own payments, then the website owner would not get their percentage.
My problem is, I don’t want to take a percentage, and I want the store vendors to process their own payments.
Seems like I might have to hire a developer for this custom feature…